SXI Pro hesitation issue

[SXIPro]

98 SXI Pro was 100% stock last year, ran like a Swiss watch. Had the head shaved and reshaped and removed the rubber silencer nozzles from the stock flame arrestors this spring. It now has has more power throughout the powerband, but it idles rough. The rough idle is no biggee, but it also has a hesitation when I go from around 1/4 throttle and I punch it. It hesitates for maybe 2 seconds then kicks in. The only thing I have tried so far is changing the plugs and cranking up the low idle screw a bit. this helped the rough idle but not the hesitation. Any ideas???

 

[sflsurfrider]

with the removal of the stock rubber silencer nozzles, you might need to lower your popoff due to less restriction.

put them back on and see if the problem clears up. if it does, you know you need to lower the popoff.

 

[JimTMich]

I agree. That will fix your problem for sure.
Then call jetworld.com and dan will set you up with springs/ n/s and possibly jets.

I'm running R&D flame arrestors and no choke plates on my stock sxi pro and Dan set me up with jets and N/S and springs and it ran perfect the first time out.

 

[w-nut]

good post i have a very slight heasatation on my 750 with a single 46 and was suspecting i had to have a play with my pop off as well ill get some springs this week and try them

 

[douglee25]

with the removal of the stock rubber silencer nozzles, you might need to lower your popoff due to less restriction.

put them back on and see if the problem clears up. if it does, you know you need to lower the popoff.

Good call SFL.

Doug

 

[SXIPro]

Just to update, SFL was right on the money. I partially blocked off the holes with duct tape where the rubber silencers were once mounted(I had mangled them into pieces when I removed them, so a re-install was a no-go)
and the hesitation was gone. So now there is this pop-off issue. The guys at Jetworld feel that if I put in size 75 pilot jets it will allow me to run without the duct tape air restriction. Or, I can leave the duct tape on and not touch the carbs. I did feel that the ski had a little less pep with the air holes restricted again, but maybe that was a placebo type effect. Any Kawi or ex-Kawi guys wanna chime in? I imagine a bunch of folks tried the 'remove the rubber nozzles' trick as it is mentioned on Group K's site as a performance mod.

 

[douglee25]

Take off the tape and lower the pop off. You should feel a performance gain feeding more air into the engine. Changing pop off isn't a big deal.

Doug

 

[ski4]

according to mikuni you can compensate pop off issues a little with a different size pilot jet

 

[JimTMich]

Dan Fitzgerald of jet-world.com says Jetting with stock exhaust, k&n's flame arrestors and no choke 75 ls jets, 155 hs jets 2.0 n/s 18psi popoff.
This is working great for me at 800 Feet above sea level.